User blog comment:Finnalca/Garbanzo the Mimikyu slayer/@comment-31267872-20180111211354

You seemed to have forgotten about Mimikyu's ability, Disguise. This allows Mimikyu a free chance to set up with Swords Dance. Mimikyu's Speed is also much higher than an Eevee's, so it will get off a hit first with a non-Ghost-type move, like Play Rough.

So, I don't know if Garbanzo will be able to take on a Mimikyu. Eevee also has (no offense) bad stats for competitive battling. If you evolve Eevee to a faster-than-Mimikyu Eeveelution, Mimikyu is now able to use a priority STAB +2 Shadow Sneak.